| Lav 56 01 Monologue The Ghost Prelude - matera Laverna.net release n.56Monologue "Perfect Imperfection" Keywords: ambient; electronica Downloads: 524 |

| matera - program_zero [Lavmix01] - matera Program zero: a dj-set for experimental dancefloor. It is the attempt to move into the creative commons dominion years of listening and dj-set, between ambient tech-house and experimentations, between dancefloor and headphones. Keywords: Experimental; Ambient; Techno; Electronica Downloads: 760 |

| vid_DMXkrew - matera DMX krew live in Dublin 31-05-2008 Keywords: elektro; funky Downloads: 100 | |

| Lav 58 Molven Network - matera last release from Molven Keywords: ambient. electronica; idm Downloads: 246 |

| Miles de personas en Magdalena (Colombia) carecen de electricidad - Antonio Matera “Se vive una grave situación en muchos municipios de Magdalena por la falta de energía eléctrica”, comentó Antonio Matera a ciudadanos de diversos municipios durante una gira departamental. “Estamos en pleno siglo XXI y hay miles de personas que carecen de un simple ventilador que les alivie y permita conciliar el sueño” sostuvo y agregó que “hay estudiantes graduándose de bachiller sin conocer un computador, y peor aún, los puestos de salud no pueden funcionar bien por la falt... Keywords: electricidad; antonio matera; magdalena; colombia; servicios basicos; luz; ventilador Downloads: 204 |

| Terra Firma - Joe Matera
Downloads: 22 |

| Fermion pairing in Bose-Fermi mixtures - F. Matera An effective interaction between fermions in a Bose-Fermi mixture is derived. It is induced by density fluctuations of the bosonic background. The contributions from states containing both one and two virtual phonons are taken into account self-consistently. The time dependence of the effective interaction has been removed by assuming that the velocity of the fermions at the Fermi surface is much larger than the sound velocity in the Bose gas... Downloads: 1 | |

| Creature Of Habit - Joe Matera
Downloads: 60 |

| nature - matera electronics The project “nature” starts in 2004, together with the netlabel, with the aim to represent the electronic sound as it was before the path that has brought it, at the end of the 90’s, to the full abstraction of its origins, towards the virtual timber. The innovative technical element often brings along aesthetic changes. The “ideal” synthetizer, able to reproduce any sound, existing or not in nature, has fed the aesthetics of subtraction as pure search for the sound, occupying the space... Downloads: 3,716 (1 review) |

| Towards a first-principles chemical engineering: Transport limitations and bistability in in situ CO oxidation at RuO2(110) - Sebastian Matera We present a first-principles based multiscale modeling approach to heterogeneous catalysis that integrates first-principles kinetic Monte Carlo simulations of the surface reaction chemistry into a fluid dynamical treatment of the macro-scale flow structures in the reactor. The approach is applied to a stagnation flow field in front of a single-crystal model catalyst, using the CO oxidation at RuO2(110) as representative example... Downloads: 4 | |

| En Magdalena, en materia de acceso vial, “estamos en una absoluta desventaja” - Antonio Matera Ramos Luego de una reciente gira por diversos municipios, Antonio Matera comentó que en materia de acceso vial y “comparado con nuestros mismos vecinos (Atlántico o Sucre), estamos en desventaja”. También agregó que es se debe y “denota falta de Gestión, indiferencia e interés por parte de nuestros dirigentes.” En el mismo sentido y en la lucha por un mejor estilo de vida para todos, invitó a la población “creer que hay otra manera de trabajar y adelantar la vida pública.” Además... Keywords: antonio matera; santa marta; colombia; acceso vial; caminos; rutas; transito; acceso Downloads: 163 |

| Antonio Matera Ramos en el corregimiento de la Avianca - Antonio Matera Ramos El candidato a la CÃ¡mara de Representantes por el Partido de la U, Antonio Matera Ramos, visitÃ³ el corregimiento de La Avianca perteneciente al Municipio de Pivijai. Keywords: antonio matera ramos; santa marta; avianca; colombia; campaÃ±a; representante a la camara; 2010 Downloads: 2 |

| Jingle de Antonio Matera Ramos - Antonio Matera Ramos Jingle de Antonio Matera Ramos para la campaña a Representante de la Cámara 2010 - 2014 Keywords: antonio matera; santa marta; colombia; acceso vial; caminos; rutas; transito; acceso; campaÃ±a; representante a la camara Downloads: 683 |

| BCS and BEC p-wave pairing in Bose-Fermi gases - F. Matera The pairing of fermionic atoms in a mixture of atomic fermion and boson gases at zero temperature is investigated. The attractive interaction between fermions, that can be induced by density fluctuations of the bosonic background, can give rise to a superfluid phase in the Fermi component of the mixture. The atoms of both species are assumed to be in only one internal state, so that the pairing of fermions is effective only in odd-l channels... Downloads: 3 | |

| Improved explicit estimates on the number of solutions of equations over a finite field - Antonio Cafure We show explicit estimates on the number of $q$--rational points of an $F_q$--definable affine absolutely irreducible variety of the algebraic closure of the finite field $F_q$ of $q$ elements. Our estimates for a hypersurface significantly improve previous estimates of W. Schmidt and M.-D. Huang and Y.-C. Wong, while in the case of a variety our estimates improve those of S. Ghorpade and G. Lachaud in several important cases... Downloads: 1 | |

| Density fluctuations and multifragmentation of nuclear matter - F. Matera The density fluctuations of nuclear matter are studied within a mean-field model in wich fluctuations are generated by an external stochastic field. The constraints imposed on the random force by the fluctuation-dissipation theorem are analyzed. It is shown that in the proximity of the borders of the spinodal region the assumption of a white-noise stochastic field can be reliably used. The domain distribution of the liquid phase in the spinodal decomposition of nuclear matter is derived... Downloads: 8 | |

| Coulomb effects on growth of instabilities in asymmetric nuclear matter - G. Fabbri We study the effects of the Coulomb interaction on the growth of unstable modes in asymmetric nuclear matter. In order to compare with previous calculations we use a semiclassical approach based on the linearized Vlasov equation. Moreover, a quantum calculation is performed within the R.P.A.. The Coulomb effects are a slowing down of the growth and the occurrence of a minimal wave vector for the onset of the instabilities... Downloads: 3 | |

| First-Principles Approach to Heat and Mass Transfer Effects in Model Catalyst Studies - Sebastian Matera We assess heat and mass transfer limitations in in situ studies of model catalysts with a first-principles based multiscale modeling approach that integrates a detailed description of the surface reaction chemistry and the macro-scale flow structures. Using the CO oxidation at RuO2(110) as a prototypical example we demonstrate that factors like a suppressed heat conduction at the backside of the thin single-crystal, and the build-up of a product boundary layer above the flat-faced surface play a... Downloads: 3 | |

| Density dependence of isospin observables in spinodal decomposition - M. Colonna Isotopic fluctuations in fragment formation are investigated in a quasi-analytical description of the spinodal decomposition scenario. By exploiting the fluctuation-dissipation relations the covariance matrix of density fluctuations is derived as a function of the wave vector for nuclear matter at given values of density, charge asymmetry, temperature, and of the time that the system spends in the instability region... Downloads: 3 | |

| When atomic-scale resolution is not enough: Spatial effects in in situ model catalyst studies - Sebastian Matera We investigate transport effects in in situ studies of defined model catalysts using a multi-scale modeling approach integrating first-principles kinetic Monte Carlo simulations into a fluid dynamical treatment. We specifically address two isothermal flow setups: i) a channel flow with the gas-stream approaching the single crystal from the side, as is representative for reactor scanning tunneling microscopy experiments; and ii) a stagnation flow with perpendicular impingement... Downloads: 1 | |

| Fast computation of a rational point of a variety over a finite field - Antonio Cafure We exhibit a probabilistic algorithm which computes a rational point of an absolutely irreducible variety over a finite field defined by a reduced regular sequence. Its time--space complexity is roughly quadratic in the logarithm of the cardinality of the field and a geometric invariant of the input system (called its degree), which is always bounded by the Bezout number of the system. Our algorithm works for fields of any characteristic, but requires the cardinality of the field to be greater t... Downloads: 8 | |

| Spinodal decomposition of expanding nuclear matter and multifragmentation - F. Matera Density fluctuations of expanding nuclear matter are studied within a mean-field model in which fluctuations are generated by an external stochastic field. Fluctuations develop about a mean one-body phase-space density corresponding to a hydrodinamic motion that describes a slow expansion of the system. A fluctuation-dissipation relation suitable for a uniformly expanding medium is obtained and used to constrain the strength of the stochastic field... Downloads: 1 | |

| Thermal entanglement in fully connected spin systems and its RPA description - Juan Mauricio Matera We examine the thermal pairwise entanglement in a symmetric system of $n$ spins fully connected through anisotropic $XYZ$-type couplings embedded in a transverse magnetic field. We consider both the exact evaluation together with that obtained with the static path + random phase approximation (RPA) and the ensuing mean field + RPA. The latter is shown to provide an accurate analytic description of both the parallel and antiparallel thermal concurrence in large systems... Downloads: 2 | |

| Even-odd entanglement in boson and spin systems - Raul Rossignoli We examine the entanglement entropy of the even half of a translationally invariant finite chain or lattice in its ground state. This entropy measures the entanglement between the even and odd halves (each forming a "comb" of $n/2$ sites) and can be expected to be extensive for short range couplings away from criticality. We first consider bosonic systems with quadratic couplings, where analytic expressions for arbitrary dimensions can be provided... Downloads: 2 | |

| Kinetic-theory approach to low-energy collective modes in nuclei - V. Abrosimov Two different solutions of the linearized Vlasov equation for finite systems, characterized by fixed and moving-surface boundary conditions, are discussed in a unified perspective. A condition determining the eigenfrequencies of collective nuclear oscillations, that can be obtained from the moving-surface solution, is studied for isoscalar vibrations of lowest multipolarity. Analytic expressions for the friction and mass parameters related to the low-enegy surface excitations are derived and the... Downloads: 1 | |

| Factorization and entanglement in general XYZ spin arrays in non-uniform transverse fields - R. Rossignoli We determine the conditions for the existence of a pair of degenerate parity breaking separable eigenstates in general arrays of arbitrary spins connected through $XYZ$ couplings of arbitrary range and placed in a transverse field, not necessarily uniform. Sufficient conditions under which they are ground states are also provided. It is then shown that in finite chains, the associated definite parity states, which represent the actual ground state in the immediate vicinity of separability, can e... Downloads: 2 | |

| Evaluation of pairwise entanglement in translationally invariant systems with the random phase approximation - Juan Mauricio Matera We discuss a general mean field plus random phase approximation (RPA) for describing composite systems at zero and finite temperature. We analyze in particular its implementation in finite systems invariant under translations, where for uniform mean fields it requires just the solution of simple local-type RPA equations. As test and application, we use the method for evaluating the entanglement between two spins in cyclic spin 1/2 chains with both long and short range anisotropic XY-type couplin... Downloads: 6 | |

| Unified semiclassical approach to isoscalar collective modes in heavy nuclei - V. I. Abrosimov A semiclassical model based on the solution of the Vlasov equation for finite systems with a sharp moving surface has been used to study the isoscalar quadrupole and octupole collective modes in heavy spherical nuclei. Within this model, a unified description of both low-energy surface modes and higher-energy giant resonances has been achieved by introducing a coupling between surface vibrations and the motion of single nucleons... Downloads: 7 | |

| Shells around black holes: the effect of freely specifiable quantities in Einstein's constraint equations - Keith Matera We solve Einstein's constraint equations in the conformal thin-sandwich decomposition to model thin shells of non-interacting particles in circular orbit about a non-rotating black hole. We use these simple models to explore the effects of some of the freely specifiable quantities in this decomposition on the physical content of the solutions. Specifically, we adopt either maximal slicing or Kerr-Schild slicing, and make different choices for the value of the lapse on the black hole horizon... Downloads: 12 | |

| Oscillations in finite Fermi systems - V. I. Abrosimov A semiclassical linear response theory based on the Vlasov equation is reviewed. The approach discussed here differs from the classical one of Vlasov and Landau for the fact that the finite size of the system is explicitly taken into account. The non-trivial problem of deciding which boundary conditions are more appropriate for the fluctuations of the phase-space density has been circumvented by studying solutions corresponding to different boundary conditions (fixed and moving surface)... Downloads: 3 | |

| Entanglement of finite cyclic chains at factorizing fields - R. Rossignoli We examine the entanglement of cyclic spin 1/2 chains with anisotropic XY Z Heisenberg couplings of arbitrary range at transverse factorizing magnetic fields. At these fields the system exhibits a degenerate symmetry-breaking separable ground state (GS). It is shown, however, that the side limits of the GS pairwise entanglement at these fields are actually non-zero in finite chains, corresponding such fields to a GS spin-parity transition... Downloads: 4 | |

| Description of thermal entanglement with the static path plus random-phase approximation - N. Canosa We discuss the application of the static path plus random phase approximation (SPA+RPA) and the ensuing mean field+RPA treatment to the evaluation of entanglement in composite quantum systems at finite temperature. These methods involve just local diagonalizations and the determination of the generalized collective vibrational frequencies. As illustration, we evaluate the pairwise entanglement in a fully connected XXZ chain of $n$ spins at finite temperature in a transverse magnetic field $b$... Downloads: 3 | |

| Separability and entanglement in finite dimer-type chains in general transverse fields - Norma Canosa We determine the conditions under which general dimer-type spin chains with $XYZ$ couplings of arbitrary range in a general transverse field will exhibit an exactly separable parity-breaking eigenstate. We also provide sufficient conditions which ensure that it will be a ground state. We then examine the exact side limits at separability of the entanglement between any two spins in a finite chain, showing that in the vicinity of separability, the system will loose all signatures of dimerization,... Downloads: 2 | |

| Polar varieties, Bertini's theorems and number of points of singular complete intersections over a finite field - Antonio Cafure Let P^n denote the n-dimensional projective space defined over the algebraic closure of a finite field F_q, let V contained P^n be a complete intersection defined over F_q of dimension r and singular locus of dimension at most s, and let \pi:V-->P^{s+1} be a "generic" linear mapping. We obtain an effective version of the Bertini smoothness theorem concerning \pi, namely an explicit upper bound of the degree of a proper Zariski closed subset of P^{s+1} which contains all the points defining singu... Downloads: 1 | |

| Evaluation of ground state entanglement in spin systems with the random phase approximation - J. M. Matera We discuss a general treatment based on the mean field plus random phase approximation (RPA) for the evaluation of subsystem entropies and negativities in ground states of spin systems. The approach leads to a tractable general method, becoming straightforward in translationally invariant arrays. The method is examined in arrays of arbitrary spin with $XYZ$ couplings of general range in a uniform transverse field, where the RPA around both the normal and parity breaking mean field state, togethe... Downloads: 1 | |

| Kinetic-theory description of isoscalar dipole modes - V. I. Abrosimov A semiclassical model, based on a solution of the Vlasov equation for finite systems with moving-surface, is employed to study the isoscalar dipole modes in nuclei. It is shown that, by taking into account the surface degree of freedom, it is possible to obtain an exact treatment of the centre of mass motion. It is also shown that a method often used to subtract the spurious strength in RPA calculations does not always give the correct result... Downloads: 2 | |

| Effects of surface vibrations on quadrupole response of nuclei - V. I. Abrosimov The effect of quadrupole-type surface vibrations on the quadrupole response function of heavy nuclei is studied by using a model based on the solution of the linearized Vlasov equation with moving-surface boundary conditions. By using a separable approximation for the residual interaction, an analytical expression is obtained for the moving-surface response function. Comparison of the fixed- and moving-surface strength functions shows that surface vibrations are essential in order to achieve a u... Downloads: 2 | |

| Relativistic Approach to Superfluidity in Nuclear Matter - F. Matera Pairing correlations in symmetric nuclear matter are studied within a relativistic mean-field approximation based on a field theory of nucleons coupled to neutral ($\sigma$ and $\omega$) and to charged ($\varrho$) mesons. The Hartree-Fock and the pairing fields are calculated in a self-consistent way. The energy gap is the result of a strong cancellation between the scalar and vector components of the pairing field... Downloads: 3 | |

| Collective motion in finite Fermi systems within Vlasov dynamics - V. I. Abrosimov A semiclassical theory of linear response in finite Fermi systems, based on the Vlasov equation, and its applications to the study of isoscalar vibrations in heavy nuclei are reviewed. It is argued that the Vlasov equation can be used to study the response of small quantum systems like (heavy) nuclei in regimes for which the finite size of the system is more important than the collisions between constituents... Downloads: 1 | |

| Singularities of symmetric hypersurfaces and an application to Reed-Solomon codes - Antonio Cafure We determine conditions on q for the nonexistence of deep holes of the standard Reed-Solomon code of dimension k over F_q generated by polynomials of degree k+d. Our conditions rely on the existence of q-rational points with nonzero, pairwise-distinct coordinates of a certain family of hypersurfaces defined over F_q. We show that the hypersurfaces under consideration are invariant under the action of the symmetric group of permutations of the coordinates... Downloads: 3 | |

| Entanglement and area laws in weakly correlated gaussian states - J. M. Matera We examine the evaluation of entanglement measures in weakly correlated gaussian states. It is shown that they can be expressed in terms of the singular values of a particular block of the generalized contraction matrix. This result enables to obtain in a simple way asymptotic expressions and related area laws for the entanglement entropy of bipartitions in pure states, as well as for the logarithmic negativity associated with bipartitions and also pairs of arbitrary subsystems... Downloads: 1 | |

| Deformation techniques for sparse systems - Gabriela Jeronimo We exhibit a probabilistic symbolic algorithm for solving zero-dimensional sparse systems. Our algorithm combines a symbolic homotopy procedure, based on a flat deformation of a certain morphism of affine varieties, with the polyhedral deformation of Huber and Sturmfels. The complexity of our algorithm is quadratic in the size of the combinatorial structure of the input system. This size is mainly represented by the mixed volume of Newton polytopes of the input polynomials and an arithmetic anal... Downloads: 2 | |

| The intrinsic complexity of parametric elimination methods - J. Heintz This paper is devoted to the complexity analysis of a particular property, called "algebraic robustness" owned by all known symbolic methods of parametric polynomial equation solving (geometric elimination). It is shown that any parametric elimination procedure which owns this property must neccessarily have an exponential sequential time complexity. Downloads: 1 | |

| Self-consistency and collective effects in semiclassical pairing theory - V. I. Abrosimov A simple model, in which nuclei are represented as homogeneous spheres of symmetric nuclear matter, is used to study the effects of a self-consistent pairing interaction on the nuclear response. Effects due to the finite size of nuclei are suitably taken into account. The semiclassical equations of motion derived in a previous paper for the time-dependent Hartree-Fock-Bogoliubov problem are solved in an improved (linear) approximation in which the pairing field is allowed to oscillate and to bec... Downloads: 2 | |

| Collective modes of asymmetric nuclear matter in Quantum HadroDynamics - V. Greco We discuss a fully relativistic Landau Fermi liquid theory based on the Quantum Hadro-Dynamics ($QHD$) effective field picture of Nuclear Matter ({\it NM}). From the linearized kinetic equations we get the dispersion relations of the propagating collective modes. We focus our attention on the dynamical effects of the interplay between scalar and vector channel contributions. A beautiful ``mirror'' structure in the form of the dynamical response in the isoscalar/isovector degree of freedom is rev... Downloads: 3 | |

| An extended Vlasov equation with pairing correlations - V. I. Abrosimov A simplified version of the Wigner--transformed time--dependent Hartree--Fock--Bogoliubov equations, leading to a solvable model for finite systems of fermions with pairing correlations, is introduced. In this model, pairing correlations result in a coupling of the Vlasov--type equation for the normal phase--space density with that for the imaginary part of the anomalous density. The effect of pairing correlations on the linear response of the system is studied for a finite one--dimensional syst... Downloads: 1 | |

| Octupole response and stability of spherical shape in heavy nuclei - V. I. Abrosimov The isoscalar octupole response of a heavy spherical nucleus is analyzed in a semiclassical model based on the linearized Vlasov equation. The octupole strength function is evaluated with different degrees of approximation. The zero-order fixed-surface response displays a remarkable concentration of strength in the $1\hbar\omega$ and $3\hbar\omega$ regions, in excellent agreement with the quantum single-particle response... Downloads: 3 | |

| Kinetic equation for finite systems of fermions with pairing - V. I. Abrosimov The solutions of the Wigner-transformed time-dependent Hartree--Fock--Bogoliubov equations are studied in the constant-$\Delta$ approximation. This approximation is known to violate particle-number conservation. As a consequence, the density fluctuation and the longitudinal response function given by this approximation contain spurious contributions. A simple prescription for restoring both local and global particle-number conservation is proposed... Downloads: 3 | |

| The hardness of polynomial equation solving - David Castro In this paper we investigate the intrinsic sequential time complexity of universal elimination procedures for arbitrary continuous data structures encoding input and output objects of elimination theory (i.e. polynomial equation systems) and admitting the representation of certain limit objects. Our main result is the following: let be given such a data structure and together with this data structure a universal elimination algorithm, say P, solving arbitrary parametric polynomial equation syste... Downloads: 3 | |

| Influence of vector interactions on the hadron-quark/gluon phase transition - G. Y. Shao The hadron-quark/gluon phase transition is studied in the two-phase model. As a further study of our previous work, both the isoscalar and isovector vector interactions are included in the Polyakov loop modified Nambu--Jona-Lasinio model (PNJL) for the quark phase. The relevance of the exchange (Fock) terms is stressed and suitably accounted for. The calculation shows that the isovector vector interaction delays the phase transition to higher densities and the range of the mixed phase correspond... Downloads: 3 | |